Manner oe closing and opening the keyhole of boor and other locks



UNITED STATES PATEN T FFICE.

DAVID EVANS, OF PHILADELPHIA, PENNSYLVANIA.

MANNER OF CLOSING AND OPENING THE KEYHOLE OF DOGR AND OTHER LOCKS.

Specification of Letters Patent No. 2,166, dated July 10, 1841.

To all 10h-0m 25 may concern Re it known that I, DAVID EVANS, of the city of Philadelphia, in the State of Pennsylvania, have invented an Improvement in the Manner of Constructing Locks for Doors, Chests, Safes, Drawers, and other Articles on which Locks are Used; and I do hereby declare that the following is a full and exact description thereof.

The main feature of this invention consists in the providing' of a sliding plate, or cover, by which the key hole is to be closed spontaneously on withdrawing the key, and that in such manner as that the key cannot be made to enter the lock until a catch is raised, and a shaft, or handle, turned, by which the plate is slid back to the required distance, when the key may be readily inserted. The part by which the catch is raised, and the handle or shaft by the revolution of which the covering plate may be made to slide back, may be varied in numerous ways, and must, in fact, be so varied in order to adapt the invention to the kind of lock employed, and the article to which it is appended. The sliding plate I caseharden, where it covers the key hole, so that it cannot be drilled or cut by any tool.

In the accompanying drawing, I have given two examples of the manner in which I apply and operate the sliding plate; one example being in the o-rdinary lock for room doors, and the other in a lock applied to an iron chest, or safe.

Figure l, represents a door lock with the inner plate removed for the purpose of showing the sliding plate, and its appendages. A, is the main bolt which is to be moved back and forth by the key, and which has not anything peculiar in its construction; in this lock, the bolt and key are supposed to be of the common kind, but bolts provided with a number of tumblers, webs, or plates, to be lifted by the key, and of any known construction or arrangement of parts may be used, my improvement being entirely independent of this part of the lock. B, is the spring bolt, which is to be turned back by means of a knob and shaft, acting on the turnbuckle or cam, C, in the usual way. To this bolt is firmly attached the metallic plate D, D, which is the sliding plate by which the key-hole is to be covered. This plate is furnished with a hole at E, through which the key must pass, and which, as represented in the drawing, is in advance of the key hole on y the plate of the lock, and therefore presents a part of its dead surface to this hole, and eti'ectually prevents the entrance of the key. The dotted lines at F, show the position of the key-hole proper, and to this position the hole E, in the plate D, must be brought before the key can be made to enter the lock; and this is effected in the following way. 0n the under side of the outer end of the spring bolt there is a notch cut which causes it, when shot forward, to latch on to the end plate G.

Fig. 2, shows the outer end of this bolt separately, having a notch at a, on its lower' side by which it is latched on to the plate G, the spring b, serving to press it down. The inortise in the plate Gr, through which the bolt passes must be of such length as to allow the bolt to be lifted up so as to free it from its hold on G, and then by turning the knob, the shaft of which passes through I-I, and retracting the spring bolt, the hole E, in the sliding plate will be brought to coincide with the key-hole of the lock, and the key may be inserted. Instead of making a notch on the lower side of the plate D, as shown by the dotted lines at c, by which the plate may be made to latch on the stud d, which will produce the same effect as that produced by the notch on the under side of the boltI B, and the operation of raising the plate and retracting the bolt, so as to cause the hole E, to coincide with the keyhole will be the same as before described.

Fig. 3, shows the manner in which the sliding plate may be applied to an iron chest, or safe, and be made to operate upon the same principle with that above described. I, I, is the frame of the door, and J, J its panels. K, K, is the middle, or lock, rail, which is composed of three, or more, thicknesses of sheet metal, the uppermost of which is removed for the purpose of showving the sliding plate by which the key-hole is to be closed. L, L, is the sliding plate, which rests upon a flat plate lvl, M, beneath it, there being a space of an eighth of an inch, or more, between the upper plate, which has been removed, and the plate M, M; said upper plate resting upon strips, or ledges, N, N, of a suitable thickness. The movable plate has two guide pins CZ, c, which enter slots made through it; the pin c, is made square, and catches into a notch in the sliding plate at f, being borne down by the spring g. The strip N, is made capable of being raised, and has a fulcrum pin at h, and a check pin at i, a spring y', serving to press itl down; is a projecting piece rising from N, and which serves to lift the sliding plate, and relieve itl from the notch f, When the strip N, is raised up, which may be done by making pressure upon its edge toward its right hand end. lf thought proper, a small portion only of the edge of the strip N, may be exposed on the lower edge of the rail of Which it makes a part. O, is a turnbuckle, or cam, to be moved by a shaft and knob when the plate L, is to be forced back for the purpose of bringing the hole Z, to correspond with the place m, of the key-hole, represented by dotted lines. From what has been said, the use and operation of the respect-ive parts above described, will be obvious.

I have spoken of, and represented, the `sliding plate as being moved by the turning of a knob and shaft, such as are ordinarily used for latches and spring bolts; but it is not intended to produce the sliding motion by their aid, in all cases, nor is it probable that they Will be most generally preferred. A ring Which forms the handle of a safe, or chest; a piece projecting from any part of the article to be locked, or a hole, or recess, into Which a piece of metal may be inserted,

so as to operate upon a turnbuckle, cam, or other analogous device, will answer the intended purpose, and it Will require but little skill in the Workman 'to produce the sliding and the lifting motions, in modes which may be varied Without end.

Having thus fully described the nature of my invention, and given exemplifications of the manner in which the same may be carried into operation, what I claim thereinv and desire to secure by Letters Patent, is-

The causing of a metallic plate to slide ove1 and to close the key-hole of a lock, in such manner as not to require any care on the part of the person withdrawing the key, so that a key cannot be inserted until said plate is removed; which removal is to be effected by the aid of tivo concurring motions, by one of Which the plate is unlatched, or released from a catch, and by the other of which it is made to slide so as to ca use a hole in said sliding plate to coincide With the key-hole; the respective parts by Which these effects are produced, being constructed, arranged, and operating substantially as herein set forth.

DAVID EVANS. 1Witnesses PETER HAY, ROBERT BERRIMAN. 

